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1.
长江口潮间带大型底栖动物群落演替 总被引:3,自引:2,他引:3
2006年1月在崇明岛西端的潮间带湿地进行了一项生态工程,经过土方工程的区域被选为大型底栖动物群落演替区,因为其中的大型底栖动物群落受到了较大破坏,在其周边未受干扰区设立对照样点。试图通过群落重建群的研究分析3个问题:(1)在群落恢复过程中不同的生态学指标如何变化?(2)群落演替过程中什么先增长,生物量还是复杂性?(3)是否可以选择生态学指标以利于演替过程中3类不同增长模式(生物量、网络结构和信息量)的识别?多变量分析用于检验被干扰区群落是否已经得到恢复。Shannon-Wiener指数、Margalef指数、Pielou均匀度指数、能质(exergy)和结构能质(Specificexergy)用于分析演替过程中群落状态的变化。结果显示物种随时间的更替与群落结构变化密切相关。物种丰富度增长迅速,而且对照区和演替区的物种组成非常相似。演替进行1个月左右之后,演替区的生物多样性已经超过了对照区。能质和结构能质提供了群落结构发展的有用信息,但仍然缺乏鉴别系统所处信息状态的能力。多样性分析结果可以从中度干扰假说(Intermediate Disturbance Hypothesis)得到很好地解释。总体而言,干扰的空间尺度决定了群落的恢复特征,如果干扰区域明显小于周边未受干扰的区域,那么群落的复杂性(信息量和网络结构)将先于生物量得到恢复。 相似文献
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Abstract. Sand dune vegetation along the coast of the Mexican states of Tabasco and Campeche was sampled by means of 1501 releves and the data were analyzed with classification and ordination programs. 36 community types were distinguished, which were grouped into 10 higher-order groups. The communities are described in a sequence reflecting the main vegetation zonation. Beach, embryo dune and foredune community groups include 12 community types, the sheltered zone includes 16 types and the fixed dunes 8 types. The ordination results reveal one main vegetation gradient corresponding to the increase in mean distance from the shoreline and elevation, and being covariant with species richness, mean vegetation cover and mean vegetation height. Additional differences are related to the geographical transition between the Gulf and Caribbean coastal vegetation and environmental conditions, mainly type of sand, occurring in the study area. Siliceous sand and a Gulf climate are characteristic for most of Tabasco, and calcareous sand and a Caribbean-type climate are characteristic for Campeche. Disturbance caused by coconut plantations, cattle grazing and tourism favours the invasion of ruderal species from waste places behind the dunes, which attain local dominance in the dunes described here. Consequently some separate community types had to be distinguished. The distribution of community types is analyzed in the context of the transitions between calcareous and siliceous substrates in the study area. 相似文献
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GABRIELA GARCÍA-MARMOLEJO GRISELDA ESCALONA-SEGURA HANS VAN DER WAL 《The Journal of wildlife management》2008,72(5):1194-1202
Abstract: Since 1997 the Mexican government has promoted Management Units for Conservation and Sustainable Use of Wildlife (UMAs) on private and community lands as an economically attractive mean for the conservation of biodiversity. To date, compliance of UMAs with stated sustainability goals has not been evaluated. Thus, we designed multicriteria evaluation framework based on the stated objectives of the national UMA program and applied it to a sample of 6 UMAs operating in peasant communities near or in the Calakmul Biosphere Reserve in Campeche, Mexico. Evaluation criteria covered thematic areas of environment, economy, social development, and laws and rules. We formulated 15 criteria with 29 indicators, and 133 verifiers. Data for the verifiers were based on direct observation, interviews with key actors in the peasant communities, participation in regional meetings, scrutiny of government reports, and databases. We calculated sustainability indexes by weighting, summing, and standardizing verifiers to percentage scales, and aggregating to the successive higher hierarchical levels of the evaluation framework. We found an average overall sustainability index of 45.7% for the UMAs evaluated. Scores were highest for the environment thematic area (55.2%), followed by economy (43.4%), social development (42.3%), and laws and rules (41.7%). We observed particularly low indicators for management strategies, habitat monitoring, environmental education, and knowledge of wildlife laws. We conclude that the contribution of UMAs to the conservation and sustainable use of biodiversity could be improved by a number of actions. These include developing wildlife management educational programs with a strong environmental legislation component, the correct enforcement of wildlife laws, and creating country-wise links among academic and governmental institutions promoting the work with regional and national wildlife experts. 相似文献
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《HOMO》2001,52(3):277-282
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José A. Alayón-Gamboa Francisco D. Gurri-García 《Human ecology: an interdisciplinary journal》2008,36(3):395-407
Energy flows were studied for the 2002–2003 agricultural cycle in four households for which agriculture is part of a diversified
survival strategy and four that practice agriculture as a business. Home garden inputs and outputs were measured monthly.
Quantified inputs were: household labour, household agro-system production, and purchased external renewable and non-renewable
energy. Outputs measured were: sales, family and animal foods. While both strategies had similar indicators in biomass and
energy production, vegetable richness, and soil quality, household garden function and sustainability differed between subsistence
and commercial householders. Subsistence gardens complemented family diet and contributed to household system resiliency.
They relied heavily on renewable energy sources from within their agro-system. Gardens in commercial households reduced fruit
tree area and increased animal husbandry for the market. They depended more on purchased non-renewable energy sources and
were less sustainable and much less energy efficient than traditional gardens.
相似文献
Francisco D. Gurri-GarcíaEmail: |
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Farrukh Baig Mirza John S. Gray 《Journal of experimental marine biology and ecology》1981,54(2):181-207
The macrobenthic fauna of the organically enriched Oslofjord was sampled in Sept.–Nov. 1977. Seventy-six stations were sampled using a stratified random plan. A total of 146 species were identified, dominated by polychaetes, molluscs and echinoderms. The faunal data were analysed by a variety of methods including diversity indices, log-normal distribution of individuals among species, factor analysis and numerical classification. The primary aim was the detection of pollution-induced disturbance and to delimit the extent of pollution on the benthic fauna of Oslofjord. All of the methods used showed a gradient from heavy pollution at the innermost part of the fjord where few species occurred, together with high dominance and low diversity, to normal unpolluted conditions at the Drøbak sill with high species diversity. From the classification analysis a combination of both site and species data revealed a trend in species groupings which were broadly similar to data from other Scandinavian fjords and from Scotland. Hydrographical and biological data taken at the turn of the century and in the 1960's compared with the present data show declining conditions in Oslofjord, due primarily to organic enrichment combined with a naturally poor water exchange which leads to stagnation of the water mass. 相似文献
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Construction activities around Campeche's central park led to the discovery of an early colonial church and an associated burial ground, in use from the mid-16th century AD to the late 17th century. Remains of some individuals revealed dental mutilations characteristic of West Africa. Analyses of strontium isotopes of dental enamel from these individuals yielded unusually high (87)Sr/(86)Sr ratios, inconsistent with an origin in Mesoamerica, but consistent with an origin in West Africa in terrain underlain by the West Africa Craton, perhaps near the port of Elmina, a principal source of slaves for the New World during the 16th century. These individuals likely represent some of the earliest representatives of the African Diaspora in the Americas. 相似文献
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J. RamosMiranda† L. Quiniou‡ D. FloresHernandez T. DoChi§ L. AyalaPerez¶ A. SosaLopez 《Journal of fish biology》2005,66(2):513-530
This study describes the current state of the nektonic communities in Terminos Lagoon in relation to the main environmental factors, and documents variations in number of fish species, dominance and abundance, compared to studies performed in 1980. Information on several environmental factors (temperature, salinity, oxygen, pH and transparency) in the Terminos Lagoon between October 1997 and March 1999 allowed the classification of the lagoon into five zones or subsystems. The hydrological characteristics of these subsystems showed spatial differences compared with studies carried out during the 1980s. During the study period, the number of fish species was 105, compared with 154 species reported in the 1980s. Five fish assemblages were identified and appeared to be associated with the five zones or subsystems. Five fish species considered important based on their abundance in the lagoon during the 1980s declined in numbers: pig fish Orthopristis chrysoptera , Atlantic croaker Micropogonias undulates , striped burrfish Chilomycterus schoepfi , spotted seatrout Cynoscion nebulosus and Gulf toadfish Opsanus beta . Six fish species, previously of minor importance, however, were very abundant: star drum Stellifer lanceolatus , Atlantic anchoveta Cetengraulis edentulus , gafftopsail catfish Bagre marinus , sand seatrout Cynoscion arenarius , striped mojarra Eugerres plumieri and ground croaker Bairdiella ronchus . Among the dominant species, the silver croaker Bairdiella chrysoura and the sea bream Archosargus rhomboidalis experienced significant changes in average abundance and distribution patterns. These changes were probably related to the impact of human activities in the Terminos Lagoon and natural variability. 相似文献
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Navarro Fernández E Pozo de la Tijera C Escobedo Cabrera E 《Revista de biología tropical》2003,51(2):591-600
We carried out surveys realized field work from March to September 2000 to get the current distribution of Cebids in the state of Campeche, Mexico. Based on interviews and direct observations. We defined the distribution of Ateles geoffroyi yucatanensis and Alouatta pigra and we documented the first time localities where Allouata palliata is found in the state. We made distributional maps of each species using vegetation overlays from Inventario Nacional Forestal (Inv For) and each point documented during fieldwork. We presented the distribution of species according to confiability of the verified or expected data. Using the attributes table of Inv For, we calculated the areas of distribution which were 22,735 km2 for Alouatta sp. and 18,501 km2 for A. g. yucatanensis. We also presented the area occupied by each species according to vegetation types and the relative proportion of these vegetation types in the state. We confirmed the ability of Alouatta sp. to survive in disturbed environments produced by habitat fragmentation, and the affinity of A. g. yucatanesis to well preserved habitats. 相似文献
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D.J. MORRISEY S. M. SAIT C. LITTLE R. S. WILSON 《Biological journal of the Linnean Society. Linnean Society of London》1994,51(1-2):247-251
The fauna of the Rivers Avon, Usk and Wye was similar to that for soft sediment in the Severn Estuary. It was dominated by Nereis diversicolor, Corophium volutator, Aiacoma balthica and oligochaetes. Maximum densities of Corophium and Macoma were higher than in the main estuary, while that of Nereis was similar. Distributions of dominant species showed gradients along river length and across river profile. These are discussed. 相似文献
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David K. A. Barnes Katrin Linse Cath Waller Simon Morely Peter Enderlein Keiron P. P. Fraser Matt Brown 《Polar Biology》2006,29(3):223-228
Benthic communities in several fjords and sheltered bays of the north coast of South Georgia Island were examined using SCUBA
and shore sampling in November 2004. It is one of the most northerly islands within the Polar Front and its well studied,
terrestrial biota is described as sub Antarctic. The intertidal and subtidal zones and their fauna are, by comparison, little
known. We describe the composition of the substratum and benthic communities of sites in several northern bays, including
an exceptional community in the extremely sheltered Moraine Fjord with a 2 m sill at its entrance. In this, like those in
some other fjordic systems, some taxa occur shallower than elsewhere, and in this instance, get large and are probably old.
Elsewhere, we found the coastal fauna was fairly similar to Antarctic shallow communities in the southern Scotia Arc and Peninsula
region. Of the taxa we found, we identified 53 to genus and 41 to species. Most of these were typical Antarctic shallow benthic
taxa. Certain flatworms, nemerteans, bivalve and gastropod molluscs, amphipod and isopod crustaceans, asteroid echinoderms
and stalked ascidians were very abundant, but some normally common Antarctic higher taxa and species were notably absent or
rare. 相似文献
16.
Vidal-Martínez VM Aguirre-Macedo ML Del Rio-Rodríguez R Gold-Bouchot G Rendón-von Osten J Miranda-Rosas GA 《Journal of helminthology》2006,80(2):159-174
The pink shrimp Farfantepenaeus duorarum may acquire pollutants, helminths and symbionts from their environment. Statistical associations were studied between the symbionts and helminths of F. duorarum and pollutants in sediments, water and shrimps in Campeche Sound, Mexico. The study area spatially overlapped between offshore oil platforms and natural shrimp mating grounds. Spatial autocorrelation of data was controlled with spatial analysis using distance indices (SADIE) which identifies parasite or pollutant patches (high levels) and gaps (low levels), expressing them as clustering indices compared at each point to produce a measure of spatial association. Symbionts included the peritrich ciliates Epistylis sp. and Zoothamnium penaei and all symbionts were pooled. Helminths included Hysterothylacium sp., Opecoeloides fimbriatus, Prochristianella penaei and an unidentified cestode. Thirty-five pollutants were identified, including polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), pesticides and heavy metals. The PAHs (2-3 ring) in water, unresolved complex mixture (UCM), Ni and V in sediments, and Zn, Cr and heptachlor in shrimps were significantly clustered. The remaining pollutants were randomly distributed in the study area. Juvenile shrimps acquired pesticides, PAHs (2-3 rings) and Zn, while adults acquired PAHs (4-5 rings), Cu and V. Results suggest natural PAH spillovers, and continental runoff of dichlorodiphenyltrichloroethane (DDT), PCBs and PAHs (2-3 ring). There were no significant associations between pollutants and helminths. However, there were significant negative associations of pesticides, UCM and PCBs with symbiont numbers after controlling shrimp size and spatial autocorrelation. Shrimps and their symbionts appear to be promising bioindicators of organic chemical pollution in Campeche Sound. 相似文献
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B. E. MARSHALL 《Freshwater Biology》1978,8(3):241-249
SUMMARY. An investigation into the ecology of benthic fauna in the eutrophic Lake McIlwaine (Rhodesia) was carried out in 1968–69. The profundal zone was only colonized in winter when the lake was isothermal and oxygen was present. The littoral zone was greatly affected by lake level fluctuation during the study period, and the population of lamellibranchs was destroyed by a drop in water level. While the water level was low, numbers of oligochaetes were high, but they declined as the water level rose. Chironomid larvae colonized the newly-flooded land and their numbers increased considerably. The effects of eutrophication were less clear but it is suggested that the presence of Chironomus in the profundal in winter, and an increase in Limnodrilus hoffmeisteri , was linked with eutrophication. 相似文献
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湛江高桥红树林湿地底栖动物粒径谱 总被引:1,自引:0,他引:1
在我国,红树林湿地底栖动物粒径谱研究很少。根据2010年1月、4月、7月、10月在湛江高桥红树林湿地获得的大型和小型底栖动物数据,构建了底栖动物生物量粒径谱,以期为湛江高桥红树林湿地的生态保护和持续利用提供科学依据。主要研究结果如下:(1)高桥红树林湿地生物量粒径谱基本为3峰模式。第一峰在-2粒级,主要由线虫构成;第二峰在4—12粒级,主要由寡毛类、多毛类和小个体甲壳类构成;第三峰在13—22粒级,主要由大个体腹足类、双壳类和甲壳类构成。(2)木榄、桐花树和无瓣海桑生境在0—4粒级之间出现一个明显的波谷,这个波谷介于线虫和寡毛类之间,是大型与小型底栖动物粒级交汇区。(3)高桥红树林湿地底栖动物正态化生物量粒径谱的斜率大于-1,截距为16.533—18.150。桐花树(Aegiceras corniculatum)和无瓣海桑(Sonneratia apetala)生境的截距、最小粒级的生物量(BMS)高于木榄(Bruguiera gymnorrhiza)和盐地鼠尾粟(Sporobolus virginicus)生境,说明桐花树和无瓣海桑生境的底栖动物生产力水平较木榄和盐地鼠尾粟生境的高;秋季的截距、BMS较其他季节高,说明秋季的底栖动物生产力水平较其他季节高。 相似文献
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The structure and diversity, including seasonal variation, and the energy budget of the benthic fauna in southern Lake Manitoba were studied and related to physical and chemical properties of the water and sediment. A total of 47 taxa were identified but 90 percent of individuals were represented by seven taxa (Candona rawsoni, Cytheromorpha fuscata, Pisidium spp., Amnicola limosa, Harnischia curtilamellata, Procladius freemani and Chironomus sp.). The spatial and temporal dynamics, dispersion patterns and life cycles of these abundant species are described.The net production was 5.05 Kcal/m2/yr for the only carnivorous species (Procladius freemani) and 28.53 Kcal/m2/yr for non-carnivorous species. The gastropod Amnicola limosa and the chironomid Chironomus sp. appear to be the most important contributors to the total biomass and net production of the community. Annual turnover rate (P/B) for all seven taxa aver-aged 2.82, with the chironomid species having the highest value and the gastropod species the lowest (3.7 and 1.75 respectively).Contribution No. 52 of the University of Manitoba Field Station (Delta Marsh). 相似文献
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Dunton K 《Trends in ecology & evolution》1992,7(6):183-189
The marine benthic fauna and flora that inhabit the shallow arctic sublittoral zone comprise a relatively young marine assemblage characterized by species of either Pacific or Atlantic affinity and notably few endemics. The young character of nearshore arctic communities, as well as their biogeographical composition, is largely a product of the Pleistocene glaciation. However, analysis of more recent collections and comparison between the origins of the benthic fauna and flora present some interesting paradoxes to biogeographers. One enigma is the low frequency of algal species with Pacific affinities in the Arctic, especially in the Chukchi, Beaufort and East Siberian Seas of the Eastern Arctic, which receive direct inputs of northward-flowing Pacific waters. In contrast, animal species with Pacific affinities are found throughout the nearshore regions of the Arctic, reaching their highest frequency in the marginal seas between the New Siberian Islands and the Canadian Archipelago. Organization of published and unpublished data, additional field collections, and the use of cladistics and molecular DNA techniques by systematists are a high priority for future research in reconstructing the evolution of the arctic biotic assemblage. 相似文献